Circuit control



March 5, 1940. B. RADTKE V 'cIRcUI'i' CONTROL Fi'led Feb. 1, 1938 flruno Baale INVENTOR. 57

E18 ATTORNEY.

Patented Mar. 5, 1940 UNITED STATES P TENT OFFICE CIRCUIT CONTRGL Bruno Eadtke, Libcrtyville, 111., assignor to The Exhibit Supply Company,.0hicago, 111. a corporation of Illinois Application Fe'bruary 1, 1938, Seiiai Nofifiiifidil 17 Claims. (01.273-438) lo'oi time 'selectively operable means for cutting shortthis periodoi time to-restore the switching "mechani s'm 'to its initialcon dition, and periodically operable switch'means'in circuit with the selectively operable-means'so that the period can- 1 notice cut short unless the selectively operable means 'isactuated at substantially the moment when the periodically operable "switch means is operated.

Another and more particularly stated object 20 is the provisionfof a control apparatus including i a main control foroperating a switch mechanism, 'a dash'potzvfor maintaining the switch mechanism in operated condition for a predetermined length of time, selectively controlled electromechanical 25 means'for rendering the dashpot inoperative-and to cut short the predetermined period, and a novel periodically operable switch'mec hanism in circuit.

with the selectively operable electromechanical means and arrangedso that theiselective oper- 30 ation of the latter must occur at. a particular time determined by the periodically 'operable'swltchmeans.

Another object of the invention is the'provision of a time-delay mechanism in the form of a dashpot or similar elastic 'fluid operated time-delay device and electromechanical valve means for controlling the action of the elastic fluid in the dashpot or time-delay device to, change the normal period of operation of the latter.

o Another object is the provision of a dashpot and electromagnetic valve'means therefor operable to change the rate of escape (or influx) of air in the dashpot and correspondingly change the normal time-delay action thereof.

-15 Yet another object is the provision of a periodically operable switch for cooperationin the aforesaid circuit control and including a closedcii cuitous raceway with a ball therein and electromagnetic means operably controlled by the weight Ln) of the ball thereagainst and effective toproject the ball repeatedly around its circuitous patlnand switch means in the path of the ball and periodically operated by'the latter as'it repeats'its circuit around the raceway.

55 In addition to the foregoing particularly describedobjects, other novel aspects of the'invention, b'oth in matters of construction and features of'operation, will appear as the following description proceeds in View of the drawing, in which: I Fig. 1 represents a fragmentary side section through a'control unit embodying the present inventionand showing part of the control mechanism in side elevation; I I Fig. is a top-plan view of the e'lectromagnetically controlled dashpot unit as viewed along lines '2-'-'2 of Fig. l and drawn to enlarged scale;

'Fig. 3 is an enlarged perspeetive'of the'switch mechanismcooperating "with the dashpot structure as seen'in Fig. 2; i 4

Fig. 4 isa topplan'view of the pericdicall'y'operable switch or ball switch, as viewed along lines Fig. 551s a diagram ofthe" entirecontrol circuit. One :of 'the'preferred embodiments of'the invention'includes' a housing it on which is mountedaimanually operable 'rec'iprocable control ll having disjoined engagement atits inner end l2 with ,one'iendportion it of a switch operating lever 'l i pivotally mounted "between its ends as at '15 on an upstanding flange plate E6 of a bracket ll conveniently mounted within the housing, A normalspring lit attached atone of its ends to the bracket Sand at its opposite end to an earfli'. oni'the lever arm M urges the-latter in an anti-cloclwvise direction into a normalposition as s een i'n'Fig. 1. i

Neariits lower end the switch operating lever orarm ld'has a lug 2t (Fig.3) extended laterally therefro'm'andsubstantially atright angles T thereto and to which is secured a fiberor other insulating plate 2! by means such as rivets '22. The lower ,end portion of the switch operating arm M is also bent at right angles thereto to providea lower offset extensionzthaving stamped therein'an elongated slot 24.

Mounted on the bracket 5'! remote from the upstanding portion l6 thereof is a time-delay device in the formof an elastic fiuid escapement mechanism such as the dashpotfli (Figs. 1 and 2). In the present embodiment, the dashpot is preferably of a type shown and described in my allowed application Serial No. 715,573 (September 2'7, 1937) {and includes a cylinder'l'fi in which is disposed a. reciprocable piston (not shown) hav- 0 ing 'a reciprocable piston rod 21 provided at its outer'free-end with'a laterally extending pin 28 which is disposed in'the elongated slot'24 in the pivotal movement of the switch operating arm l4 sets the dashpot to retard the return movement of the arm by the normal spring |8.

In operation, the dashpot or time-delay device 25 is similar to other forms of this class of device insofar as a fluid such as air or oil or the like is adapted to retard movement of a piston in proportion to the escape of the fluid from one chamber or region to another, and the present device is provided (Fig. 1) with an adjustable escapement valve 29 by means of which the ingress of air to the cylinder 26 may be controlled to vary the time-delay of the dashpot piston and rod 2'! in its movement back to normal position after having been set by an operation of the arm M.

In addition to the adjustable vent or valve means 29 of Fig. 1, there is provided an electromechanical control for the dashpot in the form of a member 30 pivotally mounted on the bracket between its ends on pin means 3| and having one of its end portions struck up to provide a lateral armature extension 32 attractable by an electromagnet 33 also mounted on the bracket IT to pivot the arm or member 30 in an anti-clockwise direction against the tension of a normal spring 34 anchored at one end 35 to the bracket and in its opposite end to an ear 36 on the member 39 and normally urging the latter in a clockwise direction so as to press a valve plug member 31, disposed on an offset portion 38 of the member 3|), firmly against an auxiliary escape vent 39 in the end wall of the dashpot. Thus, the energization of the electromagnet 33 would pivot the arm 3!! to withdraw the plug 31 from the escape vent 39 to permit a sudden influx of air into the cylinder, which in turn would permit the piston to be quickly restored to its normal position.

Mounted on the bracket H at one side of the dashpot is a bank of switches oi? the leaf spring variety, in this instance three, and each having an elongated operating spring or arm 40, 4|, or 42 extending in vertical planes along side an edge 2| of the insulating plate 2| on the switch operating arm M (Fig. 3), and each having a stationary cooperating contact spring 40', 4|, or

42', all of the contact springs being mounted on insulating means 43 in the well-known manner.

The uppermost leaf spring unit 4040 is arranged so that the end of the operating spring 40 is ofiset inwardly for engagement with the edge 2! of the insulating plate on the main switch operating arm |4 so that the contacts 4|l-40 are normally closed, whereas the other two operating springs or arms 4| and 42 are mounted so that their ofiset end portions, while similarly engaging the edge 2| of the insulating plate, are normally disposed in open circuit relation with their respective stationary contact springs 4| and 42. By virtue of this arrangement, when the switch operating arm I4 is urged in a clockwise direction by a control I, the insulating plate 2| is moved out of engagement with the respective offset end portions of the leaf spring contact assembly so that the upper switch unit 40- 15 assumes an open circuit position due to the set or bias of the spring member 4|) for this purpose, while the two lower spring units 4|-4|' and 42-42, because of their bias move into closed circuit relation, the several switches remaining in this condition until the main switch operating lever or arm I4 is permitted to return to its normal position by the dashpot 25 whereupon the switch members will be restored to their normal condition as viewed in Fig. 3.

The novel periodic switch includes in one of its forms a block 45 of wood or the like (Fig. l) mounted in an inclined position in the housing In by means of brackets 46 secured to the wall portions thereof, and as seen from above in Fig. 4, this block 45 is routed out to provide an elongated circuitous raceway 41 having an elongated central partition wall 48 on one side of which are disposed in sequence operating arms 50 of a pair of roll-over switches adapted to be operated by the passage of a ball 49 normally impounded in the raceway. These roll-over switches are also of the leaf spring variety and include a pair of light contact arms 5| and 5| (Fig. 1) and 52 and 52, the operating arms 50 of each being pivotally mounted on the block out of the raceway on bracket portions 53 with the opposite ofiset end portions of the arms 5|] extending upwardly through elongated slots in the floor of the raceway 41. As the ball 49 passes successively over the arms 50, each of the latter is depressed and r moves the contact springs 5| and 52 into contacting engagement with their cooperating springs 5| and 52.

At the lower end of the wooden block 45 and on the under side thereof, there is mounted an electromagnet 54 having an armature 55 to which is secured on insulating means 56 a pair of contact springs 51 and 58 extending in front of a relatively rigid arm 59 up through an opening in the bottom of the block for engagement ,1

with the ball 49 when the latter is in its normal position at the lower end of the raceway, the contact springs 5! and 58 being adequately light so that the weight of the ball normally urges these two contact springs together against the relatively rigid supporting arm 59. It may be remarked here that the contacts 57 and 58 are arranged in a particular manner in circuit with the electromagnet 54 such that when the latter is energized and the armature 55 pulled up, the ball 49 will be projected toward the end 41' of the raceway,

returning over the switch operating arms 50 to re-engage and close the contacts 51 and 58 (which have meanwhile opened because of the absence of the ball to energize the magnet 54) and efiect a momentary reenergization of the kicker magnet 54 to reproject the ball out over the same path, this operation being repeated so long as the main power circuit is closed through the kicker unit 54-5l-58, as will be more particularly pointed out hereinafter.

It will be apparent that the circuit of the ball 49 in the raceway 4'! is fixed and the rate of movement of the ball substantially constant within. rough limits, depending largely upon the constancy of the power source which supplies the electromagnet 54, so that the periodicity of operation of the switches 5|l-5|--5| is. substantially uniform, it being understood that this uniformity in periodic operation of these switches can be held to rather close limits depending upon the degree of constancy required.

As illustrative of the operation of the novel control circuit and apparatus, there is shown in Fig. 5 a motor 62 connected by a conductor 63 to one side of a battery 64, the opposite side of the motor being connected by a conductor 65 to the stationary contact 4| of one of the normally open leaf springs, the companion switch contact 4| of which is connected by conductor 66 to the opposite side of the battery 64. Thus, when; the springs 4|4| are closed, the motor 52 will operate, and this operation occurs when the main switch operating arm I4 is in the dotted line position shown in Fig. 1, at which time also the spring switch contacts TIL-4'2 are "closed, establishing a circuit via l. conductor 61: fIOmLQIIG side of the battery through .the switch and a :con-

ductor 68 to one side ofithekicker electromag- 6 net54, through the windingof the latteiwto the kicker arm contact58, the companion'kicker arm contact .51 being connected-by a'i'conductor '69 vto. the conductor 66 and hence to -the opposite "side of thebattery. .Thust-with thie'ma'in. switch 10 arm M in the operated or dotted line :position corresponding to closed circuit'condition of the two lowermost leaf spring tswitches, the'motor 162'will operate and the kicker'electromagnet .54 will operate periodically to project :the ball :49 '15 'aroundthe raceway 41, each time the :ball returns to close the contacts 5'l'58 the kicker 'electromagnet 54 being energized to reproject' the Lball. When the two switches 4| and 42 areclosed 0 corresponding to the dotted line position of the operating arm M, the first or upper leaf spring switch is open, but only'fora part of the predetermined period of time during which the re- :turn of the arm M to normal position. is: re- '25 tardedby'the delay device .25, it'being observed in Fig. 3 that the offset end portion of the contact spring is elongated to 'a greater degree than the corresponding offset parts 4| and 42 of the companion switches, the reason for this being that when the switchoperating arm I4 has returned part way toward normal position (depending upon. the length of the offset part of switcharm 4D) the edge 2| of the insulating plate on the arm M will engage the offset end vvof the switch arm-40 appreciably sooner than either of the otheroffset switch arm portions M or 42 so that the top switch M li! (referring now'to Fig. 5) willbeclosed while the remaining two-switches 4| and 42 are open, andthis results i in. connecting the 1 dashpot tripping magnet 33 'tozthe two ball'switch contact arms 5! and 52 by a conductor ill connected to the'switch contact 40 and a conductor 1| leading from the opposite switch contact 40 to the-magnet 33, the other 4'45 side of this magnetbeing connected to conductor 61 and hence to one side of the battery 64. The cooperating spring contacts 5! 'and52 are common1y connected by 5a conductor 12 to one contact spring '13 of .a selectively operable switch Mfiymounted above the manual control H and operable by a'button M to urge a contact l5 into circuit closing engagement with the other contact 13' and thus completea circuit via: conductor 16 back to the other side of the battery. 'It will 2: 95 be apparent that the valve operating electromag- :net 33 can be energized only when the switch contacts 40-4El are closed along with one of the two ball or periodically operable switches 5! or 52 and responsive toa closing of the switch '|3-15.

The motor 62 may be used to drive a'desired form of amusement apparatus in which an object is to stop the motorbefore the lapse of time determined by the time-delay device or'dashpot '65 12.5, butthe motor cannot be'stopped untila part of this time period has elapsed to permit the switch Ill-Ml to be .closed. Moreover, even when'the switch Ml-40' is closed, the selectively operableswitch is ineffective to stop the motor 70 unless it is actuated during one or two short periods of time when the ball 49 is passing over either of the ball switch operating arms 56. However, if the manipulator of the apparatus operates the selective. switch button M at that inl75 stant of time which satisfies the foregoing preof movement 0 requisites, thescircuit will be closed through the contact "13-l5 and either of the ball switch Icontacts' 5l-"5l or 5 2--52 and. the time-:delay controlled switch 4.ll4fl"to energize the magnet '33 and pivot the armf3il counter-clockwise '(Fig. 1'. 2) to withdraw the plug '3'! from the escapement vent 39, thereby nullifying the delaying action of theldashpot and permittinga substantially instantaneous return or the switch arm M to open the two switches l l-4.l and'dZ-AZZ', there-r10 by de-energizing the motor 52 and the ball kicker 54, whereupon the foregoing cycle of opera- :tion .may be repeated by another operation of 'eratingarm, switchmcchanism operable by said arm when the latter moves in a particular direction, time-delay means for controlling the rate said arm in said particu-lar direction, selectivel operableelectrical means fori'30 cutting short the operation of said time-delay means, a periodically operable switch means in circuit with said selectively operable means such that the latter canv be eiiectively actuated only at a particular time when said periodic switch 535 means is operated, and a controlled instrumentalityin circuit with said .iirstonentioned switch mechanism.

2. In combination, control apparatus including a controlled-electricaldevice, a tirne-delayg4n switch mechanismin circuit with said device for controlling theperiod of operation of the xelectrical means operable to -cut short the normal'period of operation of said time-delay switch .mechanism, together with selectively operable switch meansand a periodicallycperahle switch means arranged in circuit with said electrical means for cutting short the period of said timedelay switch mechanism, whereby the circuit of said controlled device may be altered only when we said selectivelyoperab-le switch means and said periodically operable switch means are actuated substantially at the same time.

3. Control mechanism including a controlled electrical instrumentality, a time-delay switch p55 arranged in circuit with said instrumentality, a

periodically. operable switch and electrically operable drive'means therefor energized through said time-delay switch selectively operable switch .rneans connected in circuit with said periodicallyqm operable switch, andelectrically operated'means vfor cutting short the normal. time-delay period of said .tin.1edelay switch to tie-energize said controlled ii'istruraentality when selectively operable switch and said periodically operable r switch lare actuated at substantially the same time.

4;. Control mechanism including a controlled electrical instrumentality, time-delay switch arranged for operation-to energize said instru T0 mentality for a predetermined period of time and provided with electrically open-ted means for cutting short said period of t to de-encrgize said instrumentality before the no rial expiration of said period, a periodically operable and elec-- 15 trically driven switch operably energized by said time-delay switch, and selectively operable switch means arranged in circuit with said electrically operated means for cutting short the time-delay period and said periodically operable switch, whereby said instrumentality may be de-energized provided said selectively operable switch means and said periodically operable switch means are actuated at substantially the same time.

5. In combination, a controlled electrical instrumentality, time-delay switch mechanism operable to energize said instrumentality for a determined length of time, an electrically driven periodically operable switch energized by said time-delay switch and having periodically open ing and closing contact means, a selectively operable switch arranged in circuit with said contact means and electromechanical means for cutting short the normal delay period of said time-delay switch, whereby said electrical instrumentality may be de-energized provided the selectively operable switch and periodically operable switch means are actuated at substantially the same time.

6. In combination, an electrically operable instrumentality and time-delay switch means for energizing the same a determined length of time, selectively operable switch means, an electrically driven periodically operable switch means energized by said time-delay switch means and arranged in circuit with said selectively operable switch means and electromagnetic mechanism cooperable with said time-delay switch means and arranged to change the normal time-delay period of said delay switch means and thus effect de-energization of said electrically operable instrumentality only when said selectively operable switch means and said periodically operable switch means are actuated together.

7. In combination, an electric motor, timedelay switch means operable to energize said motor ior a determined length of time, selectively operable switch means, electrically driven periodic switch means energized by said time-delay switch means and arranged in circuit with said selectively operable switch means for operation at substantially the same time as said periodically operable switch means to energize electrical mechanism forming part of said time-delay switch means, whereby the normal delay period of said last-mentioned switch means may be cut short to stop the operation of said motor before the conclusion of said determined length of time.

8. A controlled circuit including an electrical instrumentality, a master switch mechanism normally controlled by a dashpot and adapted to be operated to energize said instrumentality for a predetermined time, selectively operable electromagnetic means for interrupting the normal operation of said dashpot to cut short said predetermined period, said electromagnetic means including a selectively operable switch arranged in circuit with a periodically operable electrically driven switch mechanism also arranged in circuit with said instrumentality and said master switch mechanism and arranged such that actuation of said selectively operable switch will be effective to cut short the predetermined period as aforesaid only when said selectively operable switch is operated simultaneously with said periodically operable switch.

9. A control circuit including an electric motor, a master switch mechanism operable to energize said motor, an electrically driven automatic, pe riodically opening and closing switch also energized by operation of said master switch, an elastic-fluid time-delay device cooperable with said master switch to hold the same in operated condition for a determined length of time and having electromagnetically operating valve means '5 operable to cut short said period of time, a selectively operable interrupting switch said periodically operable switch being arranged in circuit with said selectively operable switch and said electromagnet means so that said electromag-g l0 netic valve means will be actuated responsive to an operation of said selectively operable switch provided the latter is operated at a time when said periodic switch is also operated.

10. Control mechanism in accordance with. claim 9 wherein said electromagnetic valve means is further controlled by said master switch in a manner such that a portion of said predetermined period of time must elapse before said selectively operable switch means can be effective for opera-= tion as set forth.

11. In. combination, a controlled electrical instrumentality, a master switch mechanism including a movable switch operating element and a plurality of switching members, means for actu- 725 ating said movable operating element to operate said switching members, means for restoring said movable operating element from switch actuating position to a normal ineffective position, dashpot means cooperable with said movable opcrating element and effective to maintain the latter in switch operating condition for a predetermined period of time, electromagnetic valve means for said dashpot and arranged for operation to cut short the normal time-delay period 15 thereof, an electrically driven periodically operating switch and with a selectively operable switch arranged in circuit with said electromagnetic valve means and efiective to energize the latter when said selectively operable switch and-40 said periodically operating switch are actuated at the same time.

12. A control circuit in accordance with claim 11 in which said periodically operating switch is energized by one of said master switching mem- 1,, bers.

13. A control circuit in accordance with claim 11 and further characterized in that said electromagnetic valve means is arranged in circuit with one of said master switching members so as to be '5 operable only during a certain part of said predetermined period of time.

14. Control means in accordance with claim 11 wherein both said periodically operating switch and said electromagnetic valve means are opera-.56 ably controlled by switching members of said master switch so as to be effective for the pur pose of cutting short said predetermined period only during a certain portion of that period.

15. Control circuit means in accordance with '00 the combination of claim 11 in which said electrically driven periodically operating switch means is in the form of a member providing a circuitous ball race with ball. operated switch means disposed in said race for actuation by said 55 ball in its circuitous movement therein, said ball operated switch means being arranged in circuit with said selectively operable switch for the purpose aforesaid, together with electromagnetic ball projecting means extending into said race and 7( provided with ball operated switch means in circuit with said electromagnetic projecting means and said master switch, a ball in said race, said race being arranged to provide a low region adjacent said projecting means, whereby said ball ll will normally be disposed against the latter and said switch means thereof, said projecting and switch. means being arranged in said circuitous path so as to be repeatedly engaged by said ball as the latter travels in its cycle so long as said electromagnetic projecting means is actuated by said master switch.

16. In combination, a dashpot provided with an air relief valve, electromagnetic means arranged to operate said valve, and switch means arranged in a control circuit with said electromag netic means and arranged to be operated during a period of time determined by said dashpot, said switch means and control circuit being arranged in such manner that the electromagnetic I means can be energized to operate said valve only during a predetermined interval in the period of operation of the dashpot and switch means.

17. In combination, a dashpot, switch means arranged to be set in closed circuit condition from a normal open circuit condition, spring means ar ranged to return the switch means to normal condition from set condition, a dashpot coacting with said switch means to regulate the rate of return to said normal condition, a normally closed air relief valve for said dashpot and adapted to be opened to hasten the restoration of said switch means to normal condition, and electrically operated means for opening said relief valve and connected in a control circuit with said switch means so that the electrically operated means can be actuated only during a certain time between the setting and restoration of said switch means.

BRUNO RADTKE. 

